Because decisions need to be made much more readily than for a position trader, order fulfillment may have a great impact on your P&L. If there are hundreds of day traders all trying to enter and exit positions simultaneously, the chances of getting filled way outside your intended price is great. For this reason you must have a sound entrance and exit strategy and become proficient in using limit and stop orders. If you try to use a market order in a fast moving stock, you may be horrified to see the slippage on your fill. This is especially true for thinly traded issues. Obtaining good fills is an absolutely crucial element of day trading volatile issues. This is why trade management is an important aspect of intraday trading.